The major components of this program include comprehensive research training under supervision of committed mentors with diverse scientific expertise, incorporation of multidisciplinary approaches to biomedical investigation, well-equipped research environment with aces to state of the art technologies, protection from distracting responsibilities, and formal didactic instruction and enrichment activities. (A) Research Areas and Disciplines: A major strength of this training program is its multidisciplinary nature. This provides ample opportunities of training across disciplines, permitting novel approaches to be applied to complex biomedical problems. Training is offered in cell and molecular biology, structural biology, photobiology, stem cell biology, genetics, genomics, metabolomics and proteomics, autoimmunity and transplantation biology, and in translational research. These disciplines are applied to nine research themes that are relevant to diseases such as diabetes, hypertension, nephritis, vasculitis and polycystic kidney disease. For those trainees opting for clinical research, enrollment in formal instructional courses in the relevant quantitative sciences is mandated. All research trainees are required to complete a revised three- component program in the responsible conduct of research. (B) Level of Training, Background and Numbers of Trainees. In this renewal, we request eight postdoctoral positions, offered to MDs, MD-PhDs or PhDs on an annual basis. In addition, we request support for a one new predoctoral position each year to be offered to an under-represented minority student completing an undergraduate degree or enrolled in graduate or medical school. We also request tuition support for formal instructional courses in the basic sciences required of MDs with no previous training in bench research but who are committed to a basic research track. (C) Training Facilities. Research training is conducted in the laboratories of the research mentors, a collaborative group of established investigators with strong training records and scientific achievements in diverse scientific disciplines. The laboratories collectively occupy 277,700 sq. ft of dedicated research space located mainly at the Massachusetts General Hospital.